All courses
Resource hub
Featured resource
Tech Upskilling Playbook 2025
Tech Upskilling Playbook

Build future-ready tech teams and hit key business milestones with seven proven plays from industry leaders.

Learn more
Hamburger Icon
  • Labs icon Lab
  • Cloud
Google Cloud Platform icon
Labs

Securely Deleting Encrypted Data on Linux

In this scenario you are the Systems Administrator for a healthcare company. Your manager has tasked you with logging into the fileserver running CentOS Linux 7.7 and securely deleting some sensitive patient data, ensuring that it cannot be easily recovered. No other files should be altered.

Get started Contact sales
Google Cloud Platform icon
Labs

Path Info

Level
Clock icon Intermediate
Duration
Clock icon 15m
Last updated
Clock icon Apr 06, 2025

Contact sales

By filling out this form and clicking submit, you acknowledge our privacy policy.

Table of Contents

  1. Challenge

    Confirm File Is Readable

    Confirm the size and permissions of the file:

    [cloud_user@$host]$ sudo ls -l /mnt/patient.1

    Show the contents of the file:

    [cloud_user@$host]$ sudo cat /mnt/patient.1

  2. Challenge

    Fill Free Space

    Be sure to double check the path, as this command does no error checking and will overwrite data:

    [cloud_user@$host]$ sudo dd if=/dev/urandom of=/mnt/junk status=progress; sync

  3. Challenge

    Overwrite File

    The shred command is the simplest method. Specifying -x ensures that the filesize remains unchanged:

    [cloud_user@$host]$ sudo shred -x /mnt/patient.1

    If the shred command is not available, we can use the following dd command:

    [cloud_user@$host]$ sudo dd if=/dev/urandom of=/mnt/patient.1 bs=45 count=1 iflag=fullblock status=progress

  4. Challenge

    Confirm File Was Overwritten and Remove

    Show file contents:

    [cloud_user@$host]$ sudo cat /mnt/patient.1

    Remove file:

    [cloud_user@$host]$ sudo rm /mnt/patient.1

  5. Challenge

    Restore Free Space

    Remove junk file:

    [cloud_user@$host]$ sudo rm /mnt/junk
Pluralsight Skills - Labs - Pluralsight
Author
Pluralsight Skills

Pluralsight Skills gives leaders confidence they have the skills needed to execute technology strategy. Technology teams can benchmark expertise across roles, speed up release cycles and build reliable, secure products. By leveraging our expert content, skill assessments and one-of-a-kind analytics, keep up with the pace of change, put the right people on the right projects and boost productivity. It's the most effective path to developing tech skills at scale.

What's a lab?

Hands-on Labs are real environments created by industry experts to help you learn. These environments help you gain knowledge and experience, practice without compromising your system, test without risk, destroy without fear, and let you learn from your mistakes. Hands-on Labs: practice your skills before delivering in the real world.

Provided environment for hands-on practice

We will provide the credentials and environment necessary for you to practice right within your browser.

Guided walkthrough

Follow along with the author’s guided walkthrough and build something new in your provided environment!

Did you know?

On average, you retain 75% more of your learning if you get time for practice.
Ready to get started?
View individual plans View team plans